[sdiy] Combined output / headphone jack?

[Neil Harper]

On 2024-10-14 18:43, grant musictechnologiesgroup.com wrote:
> Neil,
>
> The Pro-One has a mono-for-stereo-headphones/audio output jack, again
> with the NE5532:
>
> "The AUDIO OUT is a standard stereo phone jack, but it accepts a stereo
> or mono plug,
> For single-channel use with instrument amplifiers, a mono cable with
> mono plugs at
> both ends should suffice. For playing through both channels of a stereo
> amplifier, you
> will probably need a stereo cable with a stereo phone plug at one end
> and two phono
> plugs at the other. These will connect to the amplifier AUX or TAPE
> inputs, (To
> protect speakers, it is customary t o switch off the amplifier when
> making these
> connections.)
>
> Stereo headphones can be plugged directly into the AUDIO OUT jack. The
> headphones
> should have a minimum impedance of 600 Ohms,"
>
> GB


thanks Grant, that PRO-ONE implementation is even simpler..

for reference (page 2):
https://synthfool.com/docs/SequentialCircuits/Pro_One/SCI_Pro1-schematics.pdf


interestingly it uses a single cell of the 5532 only, to drive both the
L and R of the headphones, each with a 1k series resistor.

so if the PRO-ONE is going into a TS line-level jack, one of the 1k
resistors is grounded through the R to S. hmmm..

PRO-ONE was definitely built to a budget, unlike the VS... but i
actually have a single 5532 cell free on this current project, I wonder
if the PRO-ONE implementation of a output/headphone-driver would be
decent or problematic at this point.




--
/// Neil Harper
/// Every Wave is New Until it Breaks